The invention relates to electrical fixtures, and especially to the overhead mounting of lighting fixtures, fans, and the like.
Ceiling fans, pendant ceiling lamps, and the like are commonly mounted by screwing a mounting bracket or the like, attached to the fixture, to an electrical junction box set into the ceiling, which is in turn screwed to a ceiling joist or other structural member of the building. However, even if the ceiling junction box is of a sort designed and approved for the mounting of fans and other heavy fixtures, and the installation is competently installed, there is always a risk of a failure resulting in the fan or light fixture falling from the ceiling. Especially in the case of a large, heavy fan or chandelier, this may present a risk of injury to persons or damage to property underneath.
It is therefore sometimes considered desirable, and in some jurisdictions is required, to provide an alternative means of attaching the weight of the fixture to the ceiling, which bypasses the electrical box and the ceiling bracket attached to it. It has previously been proposed to achieve this by means of a tether, typically a length of wire rope, attached to the fixture, and with a loop at one end that is placed over a hook set directly into the ceiling joist through the top of the ceiling box. Thus, if the ceiling box or the bracket fails, or if the bracket is not properly attached to the ceiling box, the wire rope tethers the fixture to the ceiling. It is not necessary for the wire rope to be taut in the installed configuration. Indeed, it is probably desirable that when the fixture is hanging from the wire rope tether it drop far enough below its usual position for it to be conspicuous that the fixture is not properly mounted.
However, it has been found in practice that the loop on the tether sometimes slips off the hook while the fixture is being installed. The fact that the tether is or becomes slack when the fixture is placed in its installed position facilitates this tendency.
It is an object of the invention to attach the tether to the ceiling in such a manner that it is less likely to become detached.
In one aspect, the invention provides a hook for attaching a tether to a ceiling joist. The hook consists essentially of a length of bent wire. The hook defines a first loop adapted to lie flat against the inside of a ceiling box, or other flat surface, and to be attached to a ceiling joist through the ceiling box by a screw, the head of which bears on the sides of the first loop. The hook defines a second loop, adapted to extend downwards from the flat surface against which the first loop is screwed, and to hold the tether. One of the free ends of the length of wire extends across the second loop, so as to permit the loop of the tether to be attached to the hook but hinder it from disengaging. That free end is bent round the far side of the second loop, in such a way that if the hook tends to deform under the weight of a fixture hanging from the second loop the free end will tend to tighten on the second loop, reducing the risk that the hook will unbend and release the tether.
The one free end may be adjacent to the part of the wire forming the first loop, and may be placed across the second loop, on the side of the second loop towards the first loop, with the tip angled away from the first loop.
The one free end may be adjacent to the part of the wire forming the second loop, and may be wound loosely round the second loop, so that the tether can be hung onto the second loop by sliding it round the curve of the one free end.
In another aspect, the invention provides a ceiling-mounted electrical box provided with a safety hook according to the invention.
In a further aspect, the invention provides a ceiling-mountable electrical device, and a mounting assembly for suspended electrical devices, such as ceiling mounted lights and fans. A lower support is attached to the device, and includes a flexible tether with a looped end. An upper support is attached to the ceiling, and includes a safety hook according to the invention attached to the ceiling. The lower support is attached to the upper support. The looped end of the tether is hooked onto the safety hook. If the lower support becomes detached from the upper support, the safety hook and tether can still support the electrical device.